With the development of science and technology, many new products come into being to meet various sophisticated and diversified needs. In particular, the appearance of flexible display screen has advanced the development of new electronic products. A flexible display screen can be folded to allow one to experience two types of products: a tablet and a dual-screen cell phone, thereby increasing the value of the product and improving consumers' purchase intention.
In existing flexible display screens, the general appearance is that the middle part is curved with the two sides being flat. The shaft structures for these flexible display screens with curved middle-part and flat two-sides generally have problems. They either sacrifice the flatness of the flexible display screens to ensure the bendability of the middle parts, or sacrifice the service life to satisfy the flatness of the flexible display screens. In other words, the existing shaft structures for the flexible display screens have difficulties to balance the flatness and a long service life.